Awhile ago, I wrote a post about an app called “Wi-Fi Priority” that helped set the priority and order of your WiFi networks in iOS.
But now in iOS 11, you can now save as many WiFi networks you care to, BUT you can now tell your iPhone or iPad to not join it automatically!
Say goodbye to auto joining “Starbucks Wi-Fi” or “XFinity WiFi”!
In Settings, click on the I next to the WiFi network you do not want to auto join.
Once you click on the I. Flip the switch for auto join off!